A quad flat no-lead (QFN) package typically has a size smaller than that of a leaded chip carrier package including a plurality of pins extending outwardly. In addition, since the QFN package has a relatively short signal transmission path and a relatively high transmission speed, the QFN package is suitably applied to high frequency and high speed electronic devices.
Referring to FIG. 1, one of packaged lead frame units of a conventional QFN package includes a frame portion 11, a die pad 12 surrounded by the frame portion 11, a plurality of spaced-apart leads 13 extending from the frame portion 11 toward the die pad 12, a chip 14 mounted on the die pad 12, a plurality of wires 15 connected between the chip 14 and the leads 13, and a connecting portion 16 extending from the die pad 12 to the frame portion 11 for supporting the die pad 12.
However, since the frame portion 11 and the leads 13 are both made from metal, such as copper, a dicing tool is likely to be damaged when the packaged lead frame units are singularized by dicing along scribing lines (shown in FIG. 1 as imaginary lines that pass through the connecting portion 16 and the leads 13) with the dicing tool.